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StartsWithABang (3485481) writes On Wednesday, The Washington Post ran a story about a very large solar flare two years ago that missed Earth, but not by too much. From a scientific point of view, what is it that happens when a solar flare interacts with Earth, and what are the potential dangers to both humans and humanities infrastructure? A very good overview, complete with what you can do — as both an individual and a power company — to minimize the risk and the damage when the big one comes. Unlike asteroids, these events happen every few centuries, and in our age of electronics, would now create a legitimate disaster.

This is one of many things that causes power outages and loss of communications. In the urban areas, in the cities, people take the stability of the system for granted. Out in rural areas we live with the knowledge that the grid goes down on a regular basis and sometimes stays down for weeks. No power. No phone. No cell phone. No internet. No outside source of water, sewer, emergency services, etc. We make do. We live to survive these events. A solar storm could produce a much more significant event. People in urban areas really need to start being more prepared. The history of stability is very short.

The extent to which humanity relies on central infrastructure and stability makes me very happy, because it means that there are a few critical points of failure which allow society to be broken down and rebuilt if it becomes intolerably oppressive. However, that people can do so little for themselves means they'd also fear very much for this to happen, so they'll probably put up with a lot of boot-licking before they finally decide they've had enough.

A scenario that is purported to lead to medieval living conditions virtually overnight.

At least it's not Zombies. In fact, if you can survive the initial purge while a great percentage of survivors fight (and die) over the food & water they can find on the ground, you will stand a pretty good chance of eventually returning to civilized living.

As sad an advantage as this may seem to be, the governors will be working overtime to get back in contact with surviving taxpayers.

Done by people who either never had to go without electricity for more than 24 hours due to environmental conditions.OR WORSE - people who went through something like that without learning anything.

Every single thing made by man has multiple fail-safes built in, which have been either designed from the start OR have been evolved into the object through generations of use.Only it is so obvious to us that those parts should be there, we don't even see them now.

"And long, electricity-carrying wires spark, start fires and even operate and send signals when there’s no electricity! This even includes, believe it or not, when they aren’t plugged in."

In 1859, the "long, electricity-carrying wires" were telegraph wires, and there was nothing plugged into anyone's wall as suggested by the image in the article. Yes, there were large DC voltages induced in these miles-long wires: that's because they were MILES LONG. The wiring in your house and personal elect

You mean like at the U.S. / Mexico border? Wow - that could be entertaining to watch. I'll bring the soda if you'll bring the popcorn.

Seriously, though. Chain link fence is steel connected through a coating of zinc and its oxide. I think the resistance in that kind of fence would keep it from having any substantial currents being induced inside. If it were mounted on steel posts, or even wet wood ones, the fence would be grounded out. I'd be more concerned with the cable-TV wires: they're often not ground

All the chain link fences around here are grounded to Earth every 6ft. Obviously they're not grounded to electrical specifications, mostly because they're not intended to be electrical. Doesn't stop them from being well grounded, though.

I wouldn't rely upon the circuit breakers being able to fully protect you. If high voltages are induced on the lines, it can arc across a closed breaker. What you could do is pull the breakers out of your box - that will prevent arcing from energizing your lines, and it can also ensure that the breakers themselves aren't fried.

If you've got voltages being induced on your primary wiring much higher than the peak-to-peak of the regular supply, I think you've got much bigger things to worry about.

Telegraph wiring of the 1850s was typically connected to a battery; I imagine that the voltages induced in those long wires was overloading those batteries to the point there were fires. The batteries would have been small: big enough to work the mechanism on the other end for the receiver. Today's loading would be the equivalent of thous

And I suppose you have calculated the magnitude of the solar storms and the voltage that will travel over lines and the distance in the breaker? How can you be sure that it won't arc across the metal underneath the breaker after you've pulled the breaker? I'm not saying it will. I'm not even saying that it'll arc across the breaker, but just saying...

The meter may be owned by the utility but they can't stop me from breaking the sealing wire and yanking the thing out. I've installed the things before in new buildings so I know how it works. I even doubt they'd give me much trouble over it in the event of a large solar storm.

Came here for this, leaving satisfied.Breaking a DC current is a hell of a lot harder than an AC current since you don't have a nice zero crossing helping you out.Yanking the meter would give a really nice wide insulative gap AND, unlike throwing the breaker, pulling the meter disconnects not only the hot wire but also the neutral return, which would also be energized during such an event. If you didn't disconnect the neutral It seems possible that the neutral-ground tie would fry and start a nice fire ins

If you don't care who owns it, then being a home owner doesn't make a difference. You can go out and pull somebody's meter off your residence in an emergency the same regardless of if you're a home owner. Since the meter isn't yours, being a home owner makes as much difference as what you ate for breakfast.

Just be sure it is actually necessary, because the owner is a lot more likely to bill you if it was just paranoia.

Sheesh, the cost of putting a meter back in is practically zero. A meter has spade lugs just like the cord you plug into a wall socket. You just plug it back in place to reconnect to the grid. You probably want to call the electric company to replace the seal but I doubt they'd charge you for that, especially if you had good reason to pull it in the first place.

You're right though that you don't have to be a home owner to do that.

Most states have laws against meter tampering. By "fine" I was assuming that misdemeanors of this nature will be punished by a fine + probation and not by jail time.

Some states, such as California, have a traditional intent-based law. In California you can certainly replace the meter, unless you're doing it to reduce your rate, then it is considered tampering. However, many states have a "strict liability" anti-tampering law, where it is illegal regardless of your state of mind.

Meter tampering refers to bypassing the meter to get electricity without paying for it. Simply pulling the meter out is not tampering unless you replace it with a bypass mechanism. In the case of a solar storm I doubt they'd enforce the law against those who pulled the meter without evidence of nefarious intent as a preventative measure.

DC voltages would be blocked at the transformer. The miles-long transmission lines wouldn't carry a DC voltage into your house unless the protective gear on the pole failed somehow. The transformer itself could likely overheat leaving you without power later on.

High induced votlages in open wires are a problem, but they're not the big one.

The biggie is common-mode currents in long high-voltage transmission lines adding a strong DC component to the current in the substation transformer windings - high enough that when the same-direction peak of the AC's cycle adds to it, the core saturates. Then the inductance of the transformer drops to the air-core value and no longer substantially impeeds the current.

The current skyrockets. The resistive heating of the windings (and the force on the wires from the magnetic fields) goes up with the SQUARE of the current. The windings quickly soften, distort, form shorted turns, melt, open, short out to the frame, etc. The transformer is destroyed, or committed to a self-destructive progressive failure, in just a handful of such cycles - too fast for the circuit breakers to save them (even if they DO manage to extinguish the arcs with the substantial DC component to the current.) Even if the transformer doesn't explode and throw molten metal, gigawatt sustained arcs, and burning oil (or burning-hot oil replacement) all over the substation area, it's still dead.

This happens to MANY of the giant transformers in the power grid. Each set of three transformers that has one or more failed members means a high-voltage transmission line that is shut down until the transformer is replaced.

There are essentially no spares - these are built to order. Building one takes weeks, and there are few "production lines" so little parallelism is available. What is destroyed overnight will take years to replace, while each intercity power transmission line is not functioning until the transformers at its end ARE replaced.

The current occurs because the transformers are organized in a "Y" arrangement, and the center of the Y is grounded at each end (to prevent OTHER problems). The transformers have enough extra current handling capacity to avoid saturation from the DC through that center connection to/from ground from ordinary electrical and solar storms - just not a giant one like we get every couple centuries.

The solution is to put a resistor in that ground connection, to limit the DC in the lines (and dissipate the energy it represents). Indeed, a few lines have such resistors already.

But a suitable resistor is a box about the size of one of the transformers. It's very expensive. And it only makes a substantial difference to the operation of the lines in such a once-in-centuries event. So most executives don't spend the money (and get dinged for costing the company millions) to put them in, to prevent a failure mode that hasn't happened in the generations since Tesla and Westinghouse invented the three-phase long-line power grid.

Or at least they don't until the regulators or their stockholders require it. Which means said decision-makers need a little educational push to decide it's worth the cost and get it done.

I'm not an expert in this field, but I understand that the induced DC from a solar storm isn't as instantaneous as a lightning strike. It takes minutes to develop, which leaves time to disconnect the lines and affected transformers if they are properly monitored. As I understand, the induced DC is something on the order of hundreds of volts, which is much less than the tens of thousands of volts transmitted across ordinary high voltage transmission lines; disconnecting them should not result in arcing probl

... the induced DC from a solar storm isn't as instantaneous as a lightning strike. It takes minutes to develop, which leaves time to disconnect the lines and affected transformers if they are properly monitored.

But ARE they monitored for DC? It's not a usual problem.

Warnings on the order of minutes might be useful if the transmission line were the only one invoved. Unfortunately, the power grid is a GRID. Lots of multiple, parallel, transmission lines, and many, many, more going elsewhere and often creating loops.

Redundancy is a good thing in most situations. But when you have to drop a high line, and don't drop all the others simultaneously, you shift the load onto those that are still connected. When you're cutting off because you're near the limit - either due to heavy load at the time or because of the DC issue - you can drive the others beyond their limits (or throw things out of sync and add a bunch of "reactive current" to the load) and create a cascading failure. (Indeed, this is how the first Great Northeast Blackout occurred: Three of a set of four high-lines crossing the St. Lawrence Seaway near Niagra tripped out, and the redistributed load put one after another generator above its limits, blowing its protective breakers and making it progressively harder on those remaining.)

Gracefully shutting down the grid is not something you do on a couple minutes' notice, even if you have a plan in place.

As I understand, the induced DC is something on the order of hundreds of volts, which is much less than the tens of thousands of volts transmitted across ordinary high voltage transmission lines; disconnecting them should not result in arcing problems across the switches.

First, the problem with the induced near-DC is not the voltage, but the current. Transformers and transmission lines have as little resistance as possible, because it's pure loss of valuable energy. The magnetizing alternating current (i.e. the part of the AC that's there all the time, not just when there's a load) is also limited by the inductance of the transformers, but that doesn't impede the direct current at all. A couple hundred "DC" (very low frequency - fractional cycle per minute) volts, induced for minutes around the loop, can drive a hysterical amount of current.

Once the transformer is saturated, most of the damage comes, not from the direct current, but from the line power, which ends up dissipating lots of energy in the transformer. Meanwhile, at these voltages and currents, the switches that interrupt the AC are largely dependent on the momentary off time as the cycle reverses to quench the arc. If, say, the event happened when the line was running at about half its rated load, the direct current will be higher than the alternating current, so there will be no off time. This can keep the current flowing even through an open breaker (while dissipating megawats IN the breaker). Interrupting DC is MUCH harder than interrupting AC.

Heck, at these voltages even interrupting AC [youtube.com] is hard. (The video is of an interrupter where the jet of arc-suppressing gas failed for one leg.)

1. A few transformers (but probably only one) will be fried if the effects of a solar flare aren't noticed. (Which is unlikely because the sun is being constantly monitored for flare activity.)
2. The safety features in the rest of the grid will automatically shut transmission down if/when an affected transformer fails. (A cascading failure is fine if all you care about is protecting the grid infrastructure.)
3. The voltages induced by the

An alternative way of minimizing the effects of a severe solar storm on the grid would be placing series capacitors on the long AC transmission lines. This is done already to increase power transfer capacity of some lines.

Since the solar flare is visible many hours before CME hits, the utilities should have time to configure the grid for the storm. The oerative word here is "should".

Well, I guess I learn something new every day. Siemens sells them to power companies: they look like they'd mount on a semi with a flatbed. The installations look like banks of those mounted on a metal framework. It looks like they've installed them into lines at about 20 sites in the world. I have little doubt that would work to stop the DC current from a solar event.

Don't ask me how much an installation costs. (The website didn't have a retail price.:-) )

I first heard about use of series capacitors in an electric power systems class, 1H 1975, so they have been around for quite a while. It would seem to me that the caps should be able to withstand the DC potential set up by a Carrington event.

True, but only one of those - ACE - provides definitive storm strength and arrival time, by sampling the solar wind directly upstream of Earth for magnetic field & plasma properties (density, speed, and temperature). SOHO and STEREO let you know that something left the sun using imagery and estimate the arrival time. All of those are old NASA satellites long past their design lives, and never intended as reliable weather forcasting assets. The Deep Space Climate Observatory (DSCOVR) will take over for A

I suspect that a wiser society would have a bunch of transformers built and in storage. These days it is not only solar storms that might wreck us. The military apparently has E bombs that wipe out electronics as well as power lies. That means that an enemy will probably also have e bombs at its disposal. One unit is a miniature designed to be used in cop cars that can be aimed at a car that refuses to stop and hit it with a focused wave of power that destroys the cars electronics and brings it to

The current best way to make a large EMP, which is what we're looking for, is to burst a large thermonuclear bomb high over the target. That's going to have a whole lot of other consequences, and the people launching it are in real trouble.

And all the breakers and other fail safes kick in (I have seem thermal trips on some). The transformer is saved. Even with the last event only *one* large transformer failed and that was because the breakers failed. Oh and it was fixed/replaced routed around in just 9 hours. There was no "wait for a new one on order for weeks".

I saw a great documentary on this by Lucasfilms called "Howard the Duck" and I am prepared. Sure, they phonied it up a little bit, but the basics work for solar storms too. My Quackfu is second to no man!

But you don't have mile-long runs between towers. Induce enough voltage and you'll arc across the insulators to the support structure and ground the surge that way. There's also arc-horns and other things meant to handle breakdown in a more controlled fashion than arcing across the insulator itself.

these events happen every few centuries, and in our age of electronics, would now create a legitimate disaster.

Bullshit. The biggest problem with solar flares was its negative effect on shortwave communications. Before satellites and numerous transatlantic fiber-optic cables, that was the dominant form of military and civilian communications across large distances.

If WiFi was 30MHz, then yeah, solar flares would seriously disrupt modern communications. Since it's 2.4 or 5GHz, you'll barely notice.

This problem seems to be easily solvable by installing electronic cut-off switches near the transformers throughout the entire system. These switches could be remotely triggered by some in-band means, at least, such as an pulsing of the electrical current. This would protect homes and businesses as well as the power company infrastructure and it would seem would be a relatively inexpensive, cheap piece of electronics that could be widely deployed throughout the grid. When a solar flare is detected that woul